The amount of alcohol in your blood stream is referred to as Blood Alcohol Level (BAL). It is recorded in milligrams of alcohol per 100 milliliters of blood, or milligrams percent. For example, a BAL of .10 means that 1/10 of 1 percent (or 1/1000) of your total blood content is alcohol. When you drink alcohol it goes directly from the stomach into the blood stream. This is why you typically feel the effects of alcohol quite quickly, especially if you haven't eaten for a while. BAL depends on: 1. Amount of blood (which will increase with weight) and 2. The amount of alcohol you consume over time (the faster you drink, the higher your BAL, as the liver can only handle about a drink per hour--the rest builds up in your blood stream).
Understanding the effects of a rising BAL can be very useful in controlling drinking. Below are the consequences of various Blood Alcohol Levels,from a book by William R. Miller and Ricardo F. Munoz called, "How to Control your Drinkling: A Practical Guide to Responsible Drinking (1982):
.02 MELLOW FEELING. SLIGHT BODY WARMTH. LESS INHIBITED.
.05 NOTICEABLE RELAXATION. LESS ALERT. LESS SELF-FOCUSED. COORDINATION IMPAIRMENT BEGINS.
.08 DRUNK DRIVING LIMIT. DEFINITE IMPAIRMENT IN COORDINATION AND JUDGMENT.
.10 NOISY. POSSIBLE EMBARRASSING BEHAVIOR. MOOD SWINGS. REDUCTION IN REACTION TIME.
.15 IMPAIRED BALANCE AND MOVEMENT. CLEARLY DRUNK.
.30 MANY PASS OUT.
.40 MOST PASS OUT; SOME DIE.
.50 BREATHING STOPS. MANY DIE.
As can be seen, the most reliably pleasurable effects of alcohol occur when BAL rises to about .03-.05. Alcohol researchers have discovered that low levels of alcohol have a specific effect on thinking; alcohol results in a reduction of "self-monitoring." (Hull & Reilly, 1986). What this means is that small quantities of alcohol enable you to take your mind off yourself and your worries. Not surprisingly, this effect reduces tension...